Prey Acceptability and Preference of Oenopia conglobata (Coleoptera: Coccinellidae), a Candidate for Biological Control in Urban Green Areas.

Oenopia conglobata is one of the most common ladybird species in urban green areas of the Mediterranean region. We have obtained data about its prey acceptability and prey preferences. In a laboratory experiment, we investigated the acceptability of seven aphid and one psyllid species as prey for this coccinellid: the aphids Chaitophorus populeti, Aphis gossypii , Aphis craccivora Monelliopsis caryae , Eucallipterus tiliae , Aphis nerii (on white poplar, pomegranate, false acacia, black walnut, lime, and oleander, respectively), and the psyllid Acizzia jamatonica on Persian silk tree. These species are abundant in urban green areas in the Mediterranean region. In addition, we tested the acceptability of Rhopalosiphum padi on barley, an aphid species easily reared in the laboratory. We also tested preferences of the predator in cafeteria experiments with three aphid species and one aphid and the psyllid. Adults and larvae of the coccinellid accepted all of the preys offered, except A. nerii , with a clear preference for M. caryae . The predator also showed preference for M. caryae when it was offered in a cafeteria experiment with other aphid species or with the psyllid. The aphid R. padi obtained a good acceptability and could be used for rearing O. conglobata in the laboratory.